Press bar mechanism

ABSTRACT

A press bar mechanism includes a latch bolt attached to a housing, a pressing bar attached to the housing and coupled to the latch bolt, a rod received in the housing and coupled to the latch bolt, a casing coupled to the housing and having a chamber for receiving a hydraulic fluid, a piston is engaged in the casing and has one or more fluid flowing orifices, and the piston is smaller than the casing for forming a peripheral passage between the casing and the piston, a piston rod is attached to the piston and coupled to the rod, and a valve member is attached to the piston for blocking the orifices of the piston and for limiting the fluid to flow in one direction relative to the piston, and a spring biases the rod toward the casing for biasing the pressing bar away from the housing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a press bar mechanism for an emergencyescape or exit door or fire retardant door and exit device, and moreparticularly to a press bar mechanism including a buffering orcushioning or damping device for cushioning or damping the movement ofthe press bar and for preventing the press bar from generating sounds ornoises.

2. Description of the Prior Art

Typical emergency escape or exit doors or fire retardant doors and exitdevices comprise a press bar mechanism for being actuated by the user toopen the emergency escape or exit door or fire retardant door.

For example, U.S. Pat. No. 5,816,017 to Hunt et al., U.S. Pat. No.6,000,733 to Linder, and U.S. Pat. No. 6,945,571 to Lin disclose threeof the typical press bar devices or mechanisms each comprising a pressbar carried on a door panel, and coupled to a latch bolt with acrank-coupling mechanism, and/or one or more sliding members, forallowing the press bar to selectively actuate or operate the latch boltto release or to lock or to unlock the emergency escape or exit doors orfire retardant doors and exit devices.

However, normally, no buffering or cushioning or damping devices ormechanisms have been provided and disposed between the press bar and theemergency escape or exit door, and the press bar may have a good chanceto strike onto the emergency escape or exit door and to make or generatesounds or noises when the press bar is released by the user.

The present invention has arisen to mitigate and/or obviate theafore-described disadvantages of the conventional press bar devices ormechanisms for the emergency escape or exit doors or fire retardantdoors and exit devices.

SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a press barmechanism including a buffering or cushioning or damping device forcushioning or damping the movement of the press bar and for preventingthe press bar from generating sounds or noises.

In accordance with one aspect of the invention, there is provided apress bar mechanism comprising a housing, a latch bolt slidably attachedto the housing, a pressing bar slidably attached to the housing andmovable toward the housing and coupled to the latch bolt for selectivelyretracting the latch bolt into the housing, a rod slidably received inthe housing and coupled to the latch bolt for selectively retracting thelatch bolt into the housing, and including an extension extendedtherefrom, a hydraulic buffering device including a casing having afirst end coupled to the housing and having a chamber formed in thecasing for receiving a hydraulic fluid therein, a piston slidablyengaged in the chamber of the casing and movable toward or away from thefirst end of the casing, the piston including at least one orificeformed therein for allowing the fluid to selectively flow through theorifice of the piston, and the piston including an outer diametersmaller than an inner diameter of the casing for forming a peripheralpassage between the casing and the piston and for allowing the fluid toselectively flow through the peripheral passage that is formed betweenthe casing and the piston, a piston rod attached to the piston andextended out of the casing and coupled to the extension of the rod forallowing the piston rod and the piston to be moved relative to thecasing by the rod, and a valve member attached to the piston forselectively blocking the orifice of the piston and for preventing thefluid from flowing back through the orifice of the piston, and a springbiasing member for biasing the rod toward the casing and the latch boltand for biasing the pressing bar away from the housing, the extension ofthe rod is moved away from the casing, and the piston being moved awayfrom the first end of the casing by the piston rod and the rod when thepressing bar is depressed and moved toward the housing, and theextension of the rod is moved toward the first end of the casing whenthe pressing bar is released such that the movement of the press bar maybe cushioned and such that the press bar may be prevented fromgenerating sounds or noises.

The housing includes a frame disposed and secured therein, and the firstend of the casing is pivotally secured to the frame with a pivot axle.

The housing includes a crank pivotally coupled to the frame andpivotally coupled to the latch bolt with a link and pivotally coupled tothe pressing bar.

Further objectives and advantages of the present invention will becomeapparent from a careful reading of the detailed description providedhereinbelow, with appropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial cross sectional view of a press bar mechanism inaccordance with the present invention;

FIG. 2 is a partial cross sectional view similar to FIG. 1, illustratingthe operation of the press bar mechanism;

FIG. 3 is a partial exploded view illustrating a portion of the pressbar mechanism;

FIG. 4 is a perspective view illustrating the portion of the press barmechanism as shown in FIG. 3;

FIG. 5 is a perspective view illustrating a hydraulic buffering orcushioning or damping device of the press bar mechanism;

FIG. 6 is a cross sectional view of the hydraulic buffering orcushioning or damping device, taken along lines 6-6 of FIG. 5;

FIG. 7 is an enlarged partial cross sectional view of the hydraulicbuffering or cushioning or damping device of the press bar mechanism;

FIG. 8 is another cross sectional view similar to FIG. 6, illustratingthe operation of the hydraulic buffering or cushioning or damping deviceof the press bar mechanism; and

FIG. 9 is an enlarged partial cross sectional view of the hydraulicbuffering or cushioning or damping device as shown in FIG. 8.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, and initially to FIGS. 1 and 2, a press barmechanism 1 in accordance with the present invention comprises a base orhousing 10 for attaching to an emergency escape door or fire retardantdoor and exit device or exit door panel (not shown), and a pressing bar11 slidably attached to the housing 10 and movable or depressible towardthe housing 10 for being selectively depressed or actuated by the user,and one or more coupling or spring members 12 disposed or attachedbetween the pressing bar 11 and the exit door panel for biasing orforcing the pressing bar 11 away from the exit door panel and thehousing 10 when the pressing bar 11 is released by the user.

A lock device 20 is attached to the housing 10 and includes a latch bolt21 for selectively releasing or locking or unlocking the exit doorpanel, and includes a frame 22 disposed or attached or secured to thehousing 10, a crank 23 rotatably or pivotally coupled to the frame 22 orthe housing 10 with a pivot axle 24 and pivotally coupled to the latchbolt 21 with a link 25 and also pivotally coupled to the pressing bar 11for allowing the latch bolt 21 to be selectively moved or retracted intothe housing 10 when the pressing bar 11 is depressed toward the housing10 by the user, and for allowing the exit door panel to be selectivelyopened. The above-described structure or arrangement is typical and willnot be described in further details.

As shown in FIGS. 1-4, a longitudinal beam or rod 30 is slidablyreceived in the housing 10, and includes one end 31 pivotally coupled tothe crank 23 and/or the link 25 and/or the latch bolt 21 to selectivelymove or retract the latch bolt 21 into the housing 10, and includes astop or plate or extension 32 extended radially or outwardly from therod 30, or the extension 32 includes one end 33 attached or mounted orsecured to the rod 30 with one or more latches or fasteners 34 andincludes another end 35 located or extended away from the rod 30. Aspring biasing member 36 may further be provided and engaged with orbetween the rod 30 and the housing 10 for biasing the rod 30 toward thelock device 20 and the latch bolt 21, and for biasing the latch bolt 21to engage with the exit door panel, and also for biasing the pressingbar 11 away from the housing 10.

A hydraulic buffering or cushioning or damping device 5 is further beprovided and includes a cylindrical casing 50 having one end or firstend 51 pivotally or rotatably attached or mounted or secured or coupledto the housing 10, such as coupled to the frame 22 of the housing 10with a pivot axle 37, as shown in FIGS. 5-9, the casing 50 includes abore or chamber 52 formed therein for receiving a hydraulic oil or fluid53 therein. A piston 54 is slidably received or engaged in the chamber52 of the casing 50 and movable toward or away from the first end 51,and includes one or more orifices 55 formed therein for allowing thefluid 53 to selectively flow through the orifices 55 of the piston 54(FIGS. 6, 7), and includes an outer diameter slightly smaller than theinner diameter of the casing 50 for forming or defining a peripheral gapor passage 56 between the casing 50 and the piston 54 (FIGS. 7, 9) andfor also allowing the fluid 53 to selectively flow in either directionthrough the peripheral passage 56 that is formed between the casing 50and the piston 54.

A spring blade or check valve member 57 is attached or mounted orsecured to the piston 54 with a piston rod 58 and a fastener 59 forselectively blocking the orifices 55 of the piston 54 (FIGS. 8, 9) andfor preventing the fluid 53 from flowing through the orifices 55 of thepiston 54, such that the spring blade or check valve member 57 may actas a spring biasing means or check valve means or device for limitingthe fluid 53 to selectively flow through the orifices 55 of the piston54 in one direction only and for preventing the fluid 53 from flowingthrough the orifices 55 of the piston 54 in the other or oppositedirection. The piston rod 58 has a free end or outer end extended out ofthe casing 50 and attached or mounted or secured or coupled to the upperor other end 35 of the extension 32 of the rod 30 for allowing thepiston rod 58 and the piston 54 to be moved relative to the casing 50 bythe extension 32 of the rod 30.

In operation, as shown in FIG. 2, when the pressing bar 11 isselectively depressed or actuated by the user and moved toward thehousing 10, the latch bolt 21 may be selectively moved or retracted intothe housing 10 by the crank 23, and simultaneously, the rod 30 may beselectively moved away from the lock device 20 by the crank 23, and theextension 32 of the rod 30 may also be moved away from the lock device20 and the casing 50 of the buffering or cushioning or damping device 5.At this moment, the piston 54 may be moved or pulled or forced to moveaway from the lock device 20 by the piston rod 58 and may be movedslowly by the spring biasing member 36 and by the buffering and flowingof the fluid 53 through the orifices 55 of the piston 54 (FIGS. 6, 7).

When the pressing bar 11 is released by the user, as shown in FIG. 1,the pressing bar 11 may be moved or forced or biased away from the exitdoor panel and the housing 10 by the spring biasing member 36, and thelatch bolt 21 may be moved or forced out of the housing 10 to engagewith the exit door panel and to lock the exit door panel. At thismoment, the extension 32 of the rod 30 may be moved or forced to engagewith the piston rod 58 and to force the piston 54 to move toward thefirst end 51 of the casing 50 and to move toward the lock device 20 andthe latch bolt 21. At this moment, the spring blade or check valvemember 57 may block the orifices 55 of the piston 54 (FIGS. 8, 9) andmay prevent the fluid 53 from flowing through the orifices 55 of thepiston 54, and the fluid 53 may selectively flow through the peripheralpassage 56 that is formed between the casing 50 and the piston 54, suchthat the hydraulic buffering or cushioning or damping device 5 may beprovided for buffering or cushioning or damping or slowing the movementof the press bar 11 and for preventing the press bar 11 from generatingsounds or noises.

Accordingly, the press bar mechanism in accordance with the presentinvention includes a buffering or cushioning or damping device forcushioning or damping or slowing the movement of the press bar and forpreventing the press bar from generating sounds or noises.

Although this invention has been described with a certain degree ofparticularity, it is to be understood that the present disclosure hasbeen made by way of example only and that numerous changes in thedetailed construction and the combination and arrangement of parts maybe resorted to without departing from the spirit and scope of theinvention as hereinafter claimed.

1. A press bar mechanism comprising: a housing, a latch bolt slidablyattached to said housing, a pressing bar slidably attached to saidhousing and movable toward said housing and coupled to said latch boltfor selectively retracting said latch bolt into said housing, a rodslidably received in said housing and coupled to said latch bolt forselectively retracting said latch bolt into said housing, and includingan extension extended therefrom, a hydraulic buffering device includinga casing having a first end coupled to said housing and having a chamberformed in said casing for receiving a hydraulic fluid therein, a pistonslidably engaged in said chamber of said casing and movable toward oraway from said first end of said casing, said piston including at leastone orifice formed therein for allowing the fluid to selectively flowthrough said at least one orifice of said piston, and said pistonincluding an outer diameter smaller than an inner diameter of saidcasing for forming a peripheral passage between said casing and saidpiston and for allowing the fluid to selectively flow through saidperipheral passage that is formed between said casing and said piston, apiston rod attached to said piston and extended out of said casing andcoupled to said extension of said rod for allowing said piston rod andsaid piston to be moved relative to said casing by said rod, and a valvemember attached to said piston for selectively blocking said at leastone orifice of said piston and for preventing the fluid from flowingback through said at least one orifice of said piston, and a springbiasing member for biasing said rod toward said casing and said latchbolt and for biasing said pressing bar away from said housing, saidextension of said rod being moved away from said casing, and said pistonbeing moved away from said first end of said casing by said piston rodand said rod when said pressing bar is depressed and moved toward saidhousing, and said extension of said rod being moved toward said firstend of said casing when said pressing bar is released.
 2. The press barmechanism as claimed in claim 1, wherein said housing includes a framedisposed and secured therein, and said first end of said casing issecured to said frame with a pivot axle.
 3. The press bar mechanism asclaimed in claim 2, wherein said housing includes a crank pivotallycoupled to said frame and pivotally coupled to said latch bolt with alink and pivotally coupled to said pressing bar.